1. Field of the Invention
This invention relates to a continuous flow steam condensate removal device, and more particularly to a Venturi-type steam condensate removal device of unitary construction which is less expensive and more efficient than prior known devices.
2. Description of the Related Art
The use of devices or "steam traps" for the removal of condensate from steam lines is well known. In the past, mechanical devices which remain closed until a predetermined amount of condensate has collected therein, and periodically open to let the collected condensate pass through to a condensate receiving tank or reservoir, have been used. These devices, however, have a number of disadvantages, including initial high cost and high maintenance, repair and replacement costs. These traps also increase energy costs as a result of steam "blowing through" the relatively large open trap orifice, delays in the trap reclosing, or failure of the trap in an open condition so that the trap does not reclose at all. This "blow through" also is disadvantageous because the high temperature of the steam then tends to produce process temperature variations in associated equipment, causing reduced efficiency, and high temperatures and back pressure in the condensate receiving tank and its associated equipment.
Accordingly, more recently, Venturi-type devices of a continuous flow type have been used. For example, U.S. Pat. No. 4,171,209, issued Oct. 16, 1979, to Timothy S. Brown, discloses various Venturi-type devices (steam traps) for removing condensate from steam lines, wherein the primary feature of each device is the provision of one or more screens in an upstream passageway of the device, to filter out debris which could cause clogging of a Venturi-type orifice extending through an intermediate portion of the device. FIGS. 8 and 9 of that patent disclose a device having a unitary body with external screw threads on both ends, a Venturi-type orifice in the center of the body, and long inlet and outlet passageways. The device has a hexagonal form at its center and internal conical surfaces interconnecting the inlet and outlet passageways and the Venturi-type orifice. The unitary body is disclosed as being preferably formed of Type 304 stainlesssteel. U.S. Pat. Nos. 4,426,213 and 4,486,208, issued Jan. 17 and Dec. 4, 1984, respectively, to Constantine N. Stavropoulos, disclose similar devices having an insertable tubular nozzle structure in a unitary body.
A primary purpose of this invention is to provide a new and improved continuous flow steam condensate removal device which is less expensive, more efficient and more durable than devices of the prior art, including those disclosed in the Brown and Stavropoulos patents.